Terror struck the highly reverred Sufi shrine of Khwaja Moinuddin Chisthi in Ajmer when a bomb went off inside the complex on Thursday evening killing three persons and injuring 28 others as thousands of Muslims were breaking their day-long Ramzan fast.

A near-stampede broke out soon after the bomb kept in a school bag exploded at 1816 hours as people, who were having food after the fast, running ran helter-skelter, many of them profusely bleeding, and overturned plates and eatables lay scattered.

One of the persons killed in the low-intensity blast, which took place a few meters away from the main tomb, was identified as 45-year-old Mohammed Shoaib from Mumbai who had come to offer prayers at the dargah of the 13th century Sufi saint.

Of the injured, 14 are undergoing treatment at the local Jawaharlal Nehru Hospital and an equal number of others were dischared from the hospital after first aid.

Out of the 14 injured who are still admitted, the condition of one was critical, Rajasthan Additional Director General of Police (Law and Order) Kanhiya Lal said.

It appeared to be a pre-planned terror attack and the bomb was kept in a school bag near a tree at 'Aahetai-e-Noor' (holy place), about 10-15 feet away from main tomb of the Sufi saint, he said.

Union Home Ministry sources in Delhi said it was a terror strike in which militants had used a low-intensity improvised explosive device.

They said the terror outfits, including Pakistan-based Lashkar-e-Tayiba, were against Sufi Islam and they could be prime suspects behind the blast at the shrine, respected by both Hindus and Muslims, which came barely 10 days ahead of the meeting of Indo-Pakistan anti-terror mechanism on October 22.

Central Reserve Police Force battalions based in Ajmer had been kept in readiness for deployment at the shrine.

Rajasthan Principal Secretary (Home) V S Singh said it was a low-intensity blast and a team of forensic experts have reached the blast site.

Entry into the dargah, visited by both Hindus and Muslims, has been restricted and people are being screened, he said.

Rajasthan Chief Minister Vasundhara Raje, who is in Delhi, announced a compensation of Rs 5 lakh for the next of kin of those killed in the terror attack at the shrine of Sufi saint Khwaja Moinuddin Chisti. The seriously injured will get a relief of Rs 1 lakh each.

A high alert was sounded across Rajasthan and security at all religious places enhanced in the wake of terror attack at the dargah, Kanhaiya Lal said.

Police was asked to deploy armed men at railway stations, airports, bus stops and the state secretariat, he said.

Union Home Secretary Madhukar Gupta told reporters in Delhi that all states to intensify vigil in view of the forthcoming festive season in the wake of the blast.

Security had already been stepped up at key shrines across the country following the Mecca Masjid blast in Hyderabad in May this year.

With major Hindu and Muslim festivals round the corner starting with Eid-ul-Fitr, Gupta asked the states to maintain communal peace and harmony.

Rajasthan Home Minister Gulab Chand Katara said it has to be found out whether the incident was a result of a security lapse.

He admitted that a major chunk of the state's police force was monitoring the Gujjar agitation.

"Due to the Gujjar agitation, the security forces were busy in monitoring the situation, so they were scattered all over the state," Katara said adding, the police force was not present in large numbers at Ajmer and more specifically at the dargah.

No policeman was injured in the blast, Divisional Commissioner, Ajmer, Deepak Utpreti said.

Two or three private security guards were injured when hundreds of people rushed out of the dargah, he said.

Companies of Rajasthan Armed Constabulary were deployed in the dargah area and investigation was on by experts of Forensic Science Laboratory and intelligence agencies, including Central organisations, he added.

Utpreti who is also supervising the hospitalisation said one of the injured was very critical and senior doctors are attending on him.